Motor apparatus



2 '.Sheecs--Sheety 1 Dec. 2s, 1937.

w. H. WINEMAN MOTOR APPARATUS Filed July 21, 1933 W. H. WINEMAN MoToR APPARATUS Dec. 28, 1937.

Filed July 2l, 1933 2 SheeLs--SheefI 2 Patented Dec. 28, 1937 UNITED STATES PATENT'OFFICE MOTOR APPARATUS Wade H. Wineman, Michigan City, Ind.. assignor to Sullivan Machinery Company, a corporation o! Massachusetts Application July 31. 1933. Serial No. 681.543

14 Claims.

My invention relates to motor apparatus, and more particularly to automatic controlling means for such apparatus.

In certain oil iields there is a substantial quan- I tlty of oil available but the pressure of the oil is insuiiicient to raise the latter to the surface, and accordingly pumping devices must be used. A highly satisfactory system includes a plurality oi' pumping units all arranged within a reasonable area and all supplied with power operating medium from a central compressor having pipes leading out therefrom to the pumping units. In

a preferred form of such apparatus. the unit at each well includes a pump head in the form of an expansible chamber motor connected with a piston type pump in the well. In the interest of economy, the air is customarily preheated at the well and ls exhausted from the motor cylinders with considerable residual pressure and returned to the intake of the compressor for recompression.

As it is not practicable to keep an operator at each well, it is important, not only that the pumping apparatus at each well be of a regular and positive type and not subject to derangement. but, moreover, to provide automatic devices which will govern the speed of the pump and will automatically shut down the pump in the event of breakage ci the pump rod line or damage to the pump packings, or the like.

It is an obiect of my invention to provide an improved controlling mechanism for a pump unit of the character just mentioned, which shall operate automatically to interrupt the supply of motive tluid to the pump when necessary. It is mother object of my invention to provide an improved controlling mechanism for a pumping unit of the type referred to which shall automatically preclude overspeeding of the pump unit.

vide an improved controlling apparatus for a pump unit of the character described which shall, having once interrupted operation of the pump as a result of a' serious derangement 'of the latter, maintain the motive iluid supply to the pump interrupted until after repair of the pump and until deliberate re-starting of the pump is effected. Other objects and advantages of the present invention will subsequently appear.

In the accompanying drawings I have shown my broad invention embodied in two illustrative forms: one in which the sole function is the interruption of motive tiuid supply to'the pump and the keeping of such supply interrupted until It is a further object of the invention to pro deliberately reinitiated. after derangement of the pump mechanism; in the other form, these functions have combined with them an automatic speed governing function.

In the drawings, in which these two illustra- 5 tive embodiments are. as stated, illustrated- Fig. l is a more or less diagrammatic view. with parts broken away, of a pumping system in which the iirst illustrative form of the invention is embodied.l

Fig. 2 is a vertical central section through the automatic controlling valve which forms a part of this system.

Fig. 3 is a vertical section on the line 3-3 of Fig. 2.

Fig. 3* is a fragmentary sectional view through a portion of the upper end ot the pump cylinder.

Fig. 4 is an elevational view. with parts broken awaymof a system embodying the form of my invention in which not only automatic stopping, 20 but also automatic speed governing. is effected.

Fig. 5 is a central vertical section through the automatic controlling valve which forms a part of this last system.

Referring to the drawings. and rst to Figs. 1 25 to 3, inclusive. it will be noted that a pumping motor Il, which may advantageously be of the type disclosed in my copending application Serial No. 612,538, tiled May 20, i932, and which issued as Patent No. 2,004,146 on June 11, 1935, is sup- 3 ported in a suitable manner from a tower i2 of structural steel or the like. I'he motor ii has an automatic inlet valve mechanism i3 and an automatic discharge valve mechanism Il. Motive fluid is supplied from a central compressor system or the like (not shown) through a pipe i5, passing through a preheater I6, past a stop valve i1. a vent valve mechanism i8, and an automatic controlling mechanism i9. hereinafter more fully described, and then through a pipe 20 to the inlet valve mechanism I3. The supply pressure may be advantageously of the order of 200 to 300 pounds per square inch. Exhaust from the pumping motor il passes, under the control of the 5 exhaust valve il. through a line 2l back to the intake of the pumping system (not shown). The back pressure in the exhaust line may be perhaps 80 pounds per square inch. The pumping motor Ii comprises a cylinder member 22 within 50 which a piston I3 is reciprocable under the control of the valve mechanisms Il, I4. Ihe normal limit of upward travel of the piston II is indicated in Fig. 1, the piston usually stopping its upward travel in a position substantially below a vent port 24. A pipe 2t leads from a point substantially above the vent port. to the automatic control apparatus ll.

- The automatic control apparatus l! comprises a valve casing 21 whose opposite ends 21a. and 2lb are respectively connected. through suitable connections, with the preheater and with the Pipe line 20. A septum 23 in-the valve casing 21 provides a valve seat 29 upon 'which a valveA member 3l! is adapted to seat. 'I'he valve member 30 is supported upon the lower end ol' a valve stem 3i which passes through a gland 32 arranged in a cover member 33 for the casing 21. It will be observed that the llow through the valve casing 2l is in such a direction as to hold the valve 30 seated when it has closed. but in view of the fact that the valve when open is well above its seat and there is a pressure of between 200 and 300 pounds, say. in the valve casing, acting upon an unbalanced area equivalent to the cross sectional area of the stem 3l, the valve will remain open without dimculty. Above the casing 21 the cover member 33 supports a cylinder member 34 having a bore 35 open to the atmosphere at its lower end and containing a piston 3l which is mounted upon the valve stem 3| and adapted, through engagement with a shoulder 31 upon this stem, to move the stem down and close the valve when the piston 38 is subjected to a suillcient pressure upon its upper end. The area of the piston 38 is preferably made relatively large, so that a relatively small pressure acting downwardly upon the piston 36 will sumce to move the latter downwardly and close the valve 3l. On the other handkthe pressure built up above the piston 23 during normal upward movements o! the latter is not high enough to overcome the pressure holding valve 30 open. The cylinder head 38 is provided with a e 39 to which the pipe 25 leads, and is provided with a recess or counter-bore 40, so arranged that nearly the entire area of the upper side oi the piston 36 may be subjected continuously to the pressure transmitted through the pipe 2l.

A bypass 4I having a controlling valve 42 extends from the'space below the valve seat 23 to the space above the valve seat, for purposes which will shortly be described. A is arranged on the upper vend of the stem 3|.

I'he mode oi operation of the ilrst species of the invention will now be apparent. It will be understood that the piston 23 is connected. through a piston rod 44 and suitable connections 45, with a sucker rod line 4l leading to a positive displacement type pump discharging on the up strokes (not shown). During the normal operation of the pumping system illustrated, pressure will pass i'rom the pipe I5 through the preheater i8, through the normallyopen stop valve Il, through the vent device i3. whose vent valve is normally closed. into the casing 21, 'past the valve 3ll. which is held in raised position by the pressure within the casing. through the pipe 2l and. under the control of the admission valve mechanism I3, to the motor Il: and the motor will be operated, the piston 23 alternately rising to the position indicated in Pig. l and raising with it the pump plunger (not shown) to eiIect discharge of oil on the up stroke: and then, on opening of the exhaust valve mechanism i4, descending, with its downward movement retarded suitably by the back pressure in the pressure discharge line 2|. In the event that the -pump rod line 48 should break, or in the event that the pump packings should suddenly begin to leak seriously, the piston 23 under the relatively great handle or knob 43 pressure beneath the piston, no longer adequately offset by the load, would move upward very rapidly and create above the piston a substantial pres'- sure, due to the movement of the piston so rapidly that the open vent means 24 could not discharge the air compressed without a substantial increase in pressure. Indeed, in case the piston passed the vent port 24 a pressure of 15 pounds or more per square inch might result. During normal operation, as explained above, the vent means 24 was sumcient to prevent the building up of more than half a pound to a pound oi `pressure above atmospheric pressure above the piston 23. When the abnormal pressure is produced, however, as a result of the sudden releasing ofthe piston from the major portion o'r its load, this pressure, transmitted through the pipe 25 to the tcp of the piston 3B. will move the latter downwardly and effect closing oi' the valve 3B. The valve 38, having been moved to its seat, will be held closed by the pressure entering the casing, and accordingly there will be no tendency for this valve to be opened again except as it may be deliberately opened. When the pump rod line has been repaired or the pump cylinder removed and new packings restored and the system again placed ln working order, the operator will be able to open the valve 30, either by having the stop valve l1 closed and opening the vent i8, or by opening the bypass valve 42 and thereby equalizlng the pressure on opposite sides oi the valve 30 so that the latter may be pulled up to open position by the stem handle 43.

It will be evident that the apparatus described will normally exert no enect o n the operation c! the pumping system, but' will automatically shut down the pumping system, should the pump motor piston be relieved of its load, and will keep the pump motor shut down thereafter until an operator comes to discover and cure the dimculty which resulted in the shutting down o1' the unit.

Now turning to the second species of the invention shownthat oi' Figs. 4 and 5-in which governing as well as automatic stopping is effected, it will be observed that the pumping apparatus. in general is substantially the same as that shown in Fig. 1. In this case the automatic controlling valve mechanism is designated, generally, ll and includes a valve casing 5| having an external wall l2 bounding achamber 53 communicating with the line 2l, and an internal wall 54 bounding a chamber Il communicating with the preheater. The wall 54 has alined bores 56- and Il therein; and a valve 58 having portions ll and 4I, respectively adapted to close the openings ll and 5G. acts to control ilow o! iluid from chamber Il to chamber i3. Suitable guide ribs 3| are formed on the valve to keep it centered. The valve has a stem 32 secured thereto which extends up through a gland 33 carried by the lower endo! atrame 34, which is held by screws 4I upon the top of the casing Il. Within the upper end of the frame member 34 is a cylinder Il, in which a piston 33 is reciprocable. 'Ihe piston I4 is connected through a piston rod 33 with the stem 32.' The piston rod Il is guided in a threaded follower or abutment member lll which engages the lower end oi' a spring 'll which extends between the member ll and the lower surface of the piston 3l. The member 13 is threadedly secured in a transverse wall l2, which is of substantial thickness and provided with a series of recesses 13 in which relatively heavy springs 14 are seated. These springs extend upward a substantlal distance into the lower end oi the cylinaioaocs 3 der chamber 61. An outer cover`1l is provided for the cylinder chamber 61 and has a lock-nutheld threaded stop member 18 arranged therein and adapted to limit upward motion of the piston 68. A port 11 is connected by a line 18 with the space in the motor cylinder li, substantially above the top point in the normal travel oi the motor piston and preferably substantially above a vent 18, which is provided in the upper end oi the cylinder Ii. At the junction oi' the piston rod B9 and the valve stem 62 a washer or collar member 80 is provided, in a position to be engaged by a latch 8i pivotally connected at 82 to the bottom of the wall 12 and held by a spring 83 in position to move back into engagement with the upper part of the collar lil as soon as the latter has passed below the lower end of the latch.

'I'he mode of operation oi this safety mecha.- nism will be best understood by a description of the manner in which it is adjusted for operation. Suppose it is desired that the pump motor shall operate at the rate of l5 cycles per minute. Under these circumstances, the setscrew or stop member 16 will first be screwed down until the governor valve 58 is completely closed. The spring 1I is then adjusted to a high degree of compression by rotation of the follower 10. The motor throttle I1 is then opened wide and the stop member 16 is backed out until the governor valve is opened sufiloiently by the spring 1| to permit l5 cycles of the pump per minute. Compression of the spring 1| is then slackened by screwing out the follower until the vent pressure on top ci' the motor piston just tends to overcome the iorce exerted by the spring 1i. This vent pressure is usually only from one half to perhaps one or two pounds per square inch; but the area of the piston 68 is substantial, and therefore the pressure exerted by the latter. in the event of even a relatively small rise in the pressure above the motor piston, will easily overcome the pressure of the spring 1I and the slight addition oi unbalance due to the cross sectional area oi' the valve stem 62, and permit the throttle valve 58 to be closed. The parts are locked in the adiusted position just described.

Now ii' the pump begins to speed up on the up stroke, (this might occur if less oil were available. perhaps) the vent 19 will be inadequate to discharge the air from above the piston sumciently rapidly to preventsome rise in the pressure above the piston 6B. Accordingly, if the motor tends to speed up on its up stroke, as it would if it had a tendency to make more cycles per minute than desired, the pressure acting on the piston 68 will promptly partially close the governor valve $8 and thereby throttle the motive fluid supply and slow down the pump.

In the event that sucker rod breakage occurs, there will be a much higher upward speed of the motor piston and an almost instantaneous building up of a pressure above the motor piston sunlcient to completely close the governor valve 58. In case the piston passes vent T9, a positive compression resulting in a pressure of perhaps pounds per square inch will occur. This will operate to shut down the motor. and the motor will be held shut down because the latch 8| will enygage the ring 80 and retain the governor valve in effect closure of the valve 5B. they will eiectually cushion the downward movement of the piston 68, though they will yield sufficiently to permit the washer 80 to come below the latch 8i. Ordinary pressure variation during normal slight speed changes in the operation ot the pumping motor will not be sumcient to compress the springs 14 iar enough to allow the washer B0 to pass below the point of the latch member B i.

In Figs. l and 4 the controlling mechanisms I9 and B0 have been shown at a point more remote from the inlet valve mechanism of the pump motor than would normally'be used in practice, this being done to facilitate illustration.

From the foregoing description of the species of the invention shown -ln Figs. 4 and 5, it will be clear that I have provided a mechanism which is not only a safe automatic stop device and which is certain to shut down the motor in the event that breakage of parts causes complete closing of the governor valve, but which is also an edective governor, and which will limit the speed of the pumping motor satisfactorily and with reasonable closeness, without in any way lessening the capacity of the mechanism to serve as a stop device when that function becomes necessary.

While in this application I have specifically described two forms which my invention may assume in practice. it will be understood that these forms ot the same are shown for illustrative purposes only, and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent iszl. In a pumping system, in combination, a single acting pumping motor having a load, iiuld connections leading to said motor, controlling means for .said connections normally yieldingly maintained in now-permitting position but having associated releasable latch means by which it is held in closed position. when moved thereto. and means controlled by pressure built up in the non-working end of said pumping motor upon loss of pumping load for eiIecting movement of said controlling means to flow-interrupting position.

2. In a pumping system. in combination, a single acting pumping motor having a load, fluid connections leading to said motor, controlling means for said connections normally yieldingly maintained in flow-permitting po' ition but having when closed an unbalanced pressure area by which it is held in closed position when moved thereto, means controlled by pressure built up in the non-working end of said pumping motor upon loss of pumping load for effecting movement of said controlling means to flow-interrupting position, and means by which said unbalanced pressure area may be rendered ine'ective to hold said valve closed.

3. In a pumping system, in combination, a single acting pumping motor, a load carried thereby, iluld connections leading to the motor, valve means for controlling said connecticnaa pressure huid actuated member alined with said valve means and operatively connected thereto, means for precluding automatic value reopening when the same closes completely, and means for subjecting said duid actuated member to a compression pressure built up in said motor in the event that said motor loses its load.

4. In a pump controlling apparatus, controlling means including a valve casing. a valve seating in the direction of ilow through said casing and when closed having an unbalanced area maintaining it closed, a, valve stem, a piston mounted on said valve stern, a cylinder in which said piston is reciprocable, a single acting pumping motor supplied with operating fluid under control of said valve means and having a cylinder, a piston therein, and a connection from the non-working end of said motor cylinder to said ilrst mentioned cylinder together with means for venting normal pressure variations from said non-working end.

5. In a pumping apparatus, controlling means including a valve casing, a valve controlling ow through said casing, a valve stern, a piston mounted on said valve stern, a cylinder in which said piston is reclprocable, relatively yielding means for resiliently opposing movements of said valve by said piston insufilclent to close the former, means for presenting a relatively substantial resistance to movements of said valve to closed position, and means for precluding return of said valve to open position when once closed, a single acting pumping motor supplied with operating fluid under control of said valve means and having a cylinder and a piston in said cylinder, said motor having means for venting normal pressure variations from its non-working end, and a connection from the non-working end of said motor cylinder to said iirst mentioned cylinder.

6. In a pumping apparatus, in combination, a pumping motor having a cylinder and a piston cooperating on the working stroke of said pumping motor to displace air, means permitting displacement of the air Without the development of a substantial pressure during normal operation oi the pumping motor but insuiilcient to prevent development of progressively increasing pressure on increases in speed of piston travel above a. desired rate, and common means for controlling the normal operation of said pumping motor and for interrupting operation thereof entirely under certain conditions, including a fluid supply connection for said motor, a valve controlling said fluid supply connection, and controlling means i'or said valve including a iluid actuated member movable to close said valve, means for connecting said uid actuated member with the space from which said piston displaces iluid, means for limiting opening movement of said valve to an amount corresponding to desired maximum pumping speed, and means for yieldably resisting movement of said fluid actuated member including means providing continuously a light opposition to movement of said member in valve closing direction and-auxiliary means ineiective during minor movements of said member but presenting a stronger opposite to greater movements thereof and eii'ective to preclude valve closure thereby except upon the subjection of said member to fluid pressures attendant upon serious loss of pumping load.

7. In a. pumping apparatus, in combination, a pumping motor having a cylinder and a piston cooperating on the working stroke of said pumping motor to displace air, means permitting displacement of the air without the development of a substantial pressure during normal operation of the pumping motor, but insufficient to prevent development of progressively increasing pressure on increases in speed of piston travel above a desired rate, and means for controlling the operation of said pumping motor and for interrupting operating thereoiI entirely under certain conditions, including a iluid supply connection for said motor, a. valve controlling said nuld supply connection, and controlling means for said valve including a iluid actuated member movable to close said valve, means for connecting said fluid actuated member with the space from which said piston displaces iiuid, means for maintaining said valve closed when complete closure is attained, and means for yieldably resisting movement of said fluid actuated member eiectlve to maintain full opening at the desired speed oi motor opera.- tion but yielding if said speed is exceeded.

8. In a pumping apparatus, in combination, a pumping motor having a cylinder and a piston cooperating on the working stroke of said pumping motor to displace air, means permitting displacement oi the air Without the development oi a substantial pressure during normal operation of the pumping motor, but insuftlcient to prevent development oi' progressively increasing pressure on increases in speed of piston travel above a desired rate, and means for controlling the operation of said pumping motor and for interrupting operating thereof entirely under certain conditions, including a fluid supply connection for said motor, a valve 'controlling said fluid supply connection, and controlling means for said valve including a iluid actuated member movable to close said. valve, means for connecting said fluid actuated member with the space from which said piston displaces iluid, means for yieldably resisting movement of said fluid actuated member effective to maintain full opening at the desired speed of motor operation but yielding if said speed is exceeded, and auxiliary means for yieldingly resisting movement of said iluid actuated member to close said valve preventing valve closure except on piston travel warranting interruption of motor operation.

9. In a pumping apparatus, in combination, a pumping motor having a cylinder and a piston cooperating on the Working stroke of said pumping motor to displace air, means permitting displacement of the air without the development of a substantial pressure during normal operation or the pumping motor, but insumcient to prevent development of progressively increasing pressure on increases in speed of piston travel above a desired rate, and means for controlling the operation of said pumping motor and for interrupting operating thereof entirely under certain condii ing movement oi said iluld actuated member, and

latch means for. holding said valve closed when said yielding means yields to a. predetermined extent.

10. In a pumping apparatus, in combination, a pumping motor having a. cylinder and a piston cooperating on the working stroke of said pumping motor to displace air, means permitting displacement of the air without the development of a substantial pressure during normal operation of the pumping motor, but insumcient to prevent development of progressively increasing pressure on increases in speed of 'piston travel above a. desired rate, and means for controlling the operating oi said pumping motor and for interrupting operation thereof entirely under certain conditions, including a iluid supply connection for said motor, a valve controlling said iluid supply connection, and controlling means for said valve including a iluid actuated member movable to close said valve, means for connecting said fluid actuated member with the space from which said piston dlsplaces fluid, means for yieldably resisting movement of said fluid actuated member, latch means for holding said valve closed when said yielding means yields to a predetermined extent, and yielding means for preventing yielding of said first mentioned yielding means enabling said valve to move sufllciently to permit operation of said latch means during slight pis- Aton overspeeding.

l1. In a pumping system, in combination, a single acting pumping motor having a pressure fluid moved work performing element, a pumping load moved thereby, fluid supply connections for the motor, and controlling means for said connections including a supply throttling and interrupting valve having means for yieldably maintaining the same normally open and means for maintaining the same closed, whenever moved to closed position, irrespective of cessation of the operating condition which effected closure, and means for partially closing the same on small reduction in pumping load to eect partially throttled but continued supply and complete closure on substantially complete loss of pumping load.

12. In a pumping system. in combination, a. single acting pumping motor having a pressure fluid moved work performing element, a pumping load moved thereby, fluid supply connectins for the motor, and controlling means for said connections including a supply throttling and interrupting valve having means for maintaining the same closed, whenever moved to closed position. irrespective ot cessation of the operating condition which efiected closure. and means actuated by iluid displaced by the pressure fluid moved work performing element for partially pai-.ens No. 2,103,965.

WADE H WINEMAN.

closing said valve means on small reduction in pumping load, to eiiect partially throttled but continued supply, and complete closure on substantially complete loss of pumping load.

13. In a pumping system. in combination, a single acting pumping motor, a pumping load connected thereto by a rod line, a source of operating fluid supply for said pumping motor, and a single control valve intermediate said supply and motor including valve means having a pressure fluid control responsive to speed changes occurring during each single power stroke of the pumping motor and movable in a closing direction to accommodate and adjust iluid supply in accordance with any normal speed variations without closure, but completely closable on motor movement following rod line breakage and having means for maintaining the same closed until said means is rendered ineffective by intervention from outside said system.

14. In a pumping system. in combination, a single acting pumping motor having relatively movable cylinder and piston elements, a pumping load moved by said motor. said cylinder element having a connection for the discharge of uid from the non-working end thereof during moving oi' said pumping load by said motor, a fluid supply for said motor. and a valve for throttling or completely interrupting fluid supply to said motor, said valve having provision for maintainz' ing the same closed, whenever the same is moved to closed position, until said provision is rendered ineffective by intervention from outside said system, and means actuated by fluid discharged through said connection for partially closing said valve on. small reduction in pumping load, to eect partially restricted but continued supply of operating duid to said motor. and to eflect complete closure of said valve upon substantially complete loss of pumping load.

WADE H. WINEMAN.

CERTIFICATE OF CORRECTIN December 28 1957,

Ithis hereby lcertified that error appears" in the printed specification of the above numbered patent requiring correction as follows: Page 5,' second column, line 69, claim 5, for the word "value" read valve; and that the said Letters Patent shouldbe read with this correction therein that the same may conform to the record of the case in the yPatent Office. I

Signed and sealed this 1st day of March, A. D. 1938.

(Seal) Henry Van Aradale, Acting Commissioner o-f Patents.

nection, and controlling means for said valve including a iluid actuated member movable to close said valve, means for connecting said fluid actuated member with the space from which said piston dlsplaces fluid, means for yieldably resisting movement of said fluid actuated member, latch means for holding said valve closed when said yielding means yields to a predetermined extent, and yielding means for preventing yielding of said first mentioned yielding means enabling said valve to move sufllciently to permit operation of said latch means during slight pis- Aton overspeeding.

l1. In a pumping system, in combination, a single acting pumping motor having a pressure fluid moved work performing element, a pumping load moved thereby, fluid supply connections for the motor, and controlling means for said connections including a supply throttling and interrupting valve having means for yieldably maintaining the same normally open and means for maintaining the same closed, whenever moved to closed position, irrespective of cessation of the operating condition which effected closure, and means for partially closing the same on small reduction in pumping load to eect partially throttled but continued supply and complete closure on substantially complete loss of pumping load.

12. In a pumping system. in combination, a. single acting pumping motor having a pressure fluid moved work performing element, a pumping load moved thereby, fluid supply connectins for the motor, and controlling means for said connections including a supply throttling and interrupting valve having means for maintaining the same closed, whenever moved to closed position. irrespective ot cessation of the operating condition which efiected closure. and means actuated by iluid displaced by the pressure fluid moved work performing element for partially pai-.ens No. 2,103,965.

WADE H WINEMAN.

closing said valve means on small reduction in pumping load, to eiiect partially throttled but continued supply, and complete closure on substantially complete loss of pumping load.

13. In a pumping system. in combination, a single acting pumping motor, a pumping load connected thereto by a rod line, a source of operating fluid supply for said pumping motor, and a single control valve intermediate said supply and motor including valve means having a pressure fluid control responsive to speed changes occurring during each single power stroke of the pumping motor and movable in a closing direction to accommodate and adjust iluid supply in accordance with any normal speed variations without closure, but completely closable on motor movement following rod line breakage and having means for maintaining the same closed until said means is rendered ineffective by intervention from outside said system.

14. In a pumping system. in combination, a single acting pumping motor having relatively movable cylinder and piston elements, a pumping load moved by said motor. said cylinder element having a connection for the discharge of uid from the non-working end thereof during moving oi' said pumping load by said motor, a fluid supply for said motor. and a valve for throttling or completely interrupting fluid supply to said motor, said valve having provision for maintainz' ing the same closed, whenever the same is moved to closed position, until said provision is rendered ineffective by intervention from outside said system, and means actuated by fluid discharged through said connection for partially closing said valve on. small reduction in pumping load, to eect partially restricted but continued supply of operating duid to said motor. and to eflect complete closure of said valve upon substantially complete loss of pumping load.

WADE H. WINEMAN.

CERTIFICATE OF CORRECTIN December 28 1957,

Ithis hereby lcertified that error appears" in the printed specification of the above numbered patent requiring correction as follows: Page 5,' second column, line 69, claim 5, for the word "value" read valve; and that the said Letters Patent shouldbe read with this correction therein that the same may conform to the record of the case in the yPatent Office. I

Signed and sealed this 1st day of March, A. D. 1938.

(Seal) Henry Van Aradale, Acting Commissioner o-f Patents. 

